Laboratory testing-based valve prognostics

ABSTRACT

The claimed method and system develops a useful lifetime profile for a component of a process control device, such as a valve, and uses that lifetime profile to determine a projected remaining lifetime for the device component in operation. The lifetime profile is developed from using real world operational data of similar process control devices, used under substantially the same operating conditions as to be experienced during operation. Profiles may be developed for numerous device components, from which a projected lifetime profile for the entire process control device is developed. Based on the projected remaining lifetime, notification warnings may be sent to remote computers and maintenance scheduling may be automatically achieved.

RELATED APPLICATIONS

This application claims the benefit of priority of U.S. ProvisionalPatent Application 61/785,073, filed Mar. 14, 2013, entitled “LaboratoryTesting-Based Valve Prognostics,” which application is herebyincorporated herein by reference in its entirety and for all purposes.

FIELD OF TECHNOLOGY

The present disclosure relates to process control devices within processplants and, more specifically, to techniques for performing lifetimeprognostics on the process control devices.

BACKGROUND

Existing process control systems may perform periodic diagnostics onprocess control devices, such as valves, to determine the operabilityand performance of such devices. Determining the operability of aprocess control device may permit better scheduling of maintenance ofthe process control device, thereby decreasing failure occurrences anddown time. This may result in increased efficiency, safety, and revenue.The process control systems may use various sensors and othermeasurement devices to observe characteristics of a process controldevice. For example, some existing control systems may use a digitalvalve controller to measure and collect data from various sensors on acontrol valve.

Among the uses of data collected from control valves, customers desirethe data to plan preventative maintenance for their process plants,hoping to avoid unplanned maintenance and loss of production cause byunexpected failures. Customers, for example, will want to know theprojected life span of a valve, before requiring maintenance, as well aswhat repair procedures and replacement options are available andrecommended. For the manufacturer, providing a precise life spanprediction is challenging because actual process conditions will varydramatically from customer to customer, or facility to facility, evenwithin a processing plant. Specification sheets may be provided to thecustomers providing some projection data, and sometimes in response tocustomer provided design conditions. However, factors such astemperature and pressure often vary dramatically from those provided inthe design conditions from the customer and either way, other varyingconditions such as fluid state (liquid or vapor) and impurities (solid,liquid, or vapor) are typically not provided in the design conditions,or, as with the other factors, can vary considerably during actual use.

Conventionally, service and repair history data from customers would becollected to create Mean Time To Failure (MTTF) and Mean Time BetweenFailure (MTBF). This MTTF and MTBF data could then be used forpredicting life span of a valve. Using this historical data can belimiting, however, because maintenance records may be incomplete ornon-existent. Furthermore, customers may not desire to share suchinformation out of a concern that their operating conditions would bedisclosed to their competitors. The result is that MTTF and MTBF data,based on historical data, are often incomplete and not sufficientlyinformative.

Another technique for predicting MTTF and MTBF is through the use oflaboratory data produced in conditions as closely approximating reallife conditions as possible. Pressure and temperature conditions areusually easy to achieve in a well-equipped lab. Fluid properties andcontaminations, however, are much more difficult to simulate; althoughthe essential fluid properties typically can be achieved, i.e.,oxidizing, non-oxidizing, wet, dry, lubricating and non-lubricating.Occasionally, even a known contamination can be achieved such as withparticulates in the fluid stream. Laboratory cycle testing inparticular, e.g., at the same temperature, pressure and fluid propertiesthat represent particular valve service applications, can be aneffective ersatz for actual field data. This is especially the case forvalve components that are subject to normal mechanical wear or fatigue.

While laboratory testing is used, for the foregoing and other reasons,conventional testing methods of determining MTTF and MTBF are lacking.The methods are unable to account for the varied conditions and variousfactors that affect device life span, particularly, those relating tosliding stem valves and rotary valves, where the various components thatcan wear or fatigue, resulting in valve failure, are many and each withpotentially different responses to operating conditions, such astemperature, pressure, fluid, etc.

SUMMARY OF THE INVENTION

In accordance with an example, a method for developing a projectedlifetime profile for a component of a process control device isprovided. The method may include receiving an identification of acomponent capable of experiencing mechanical wear or fatigue, over time,during operation of the process control device, and receiving anoperating parameter corresponding to the component. That componentperformance degrades over time as a result of the changing values ofthat operating parameter. The method may include receivingpreviously-recorded performance data of a reference component collectedduring operation of the reference component under conditions compatiblewith conditions under which the process control device is to operate.The method may further include developing the projected lifetime profilefor the component based on the previously-recorded performance data,wherein the projected lifetime profile indicates a projected lifetime ofthe component as a function of values of the operating parameter.

In accordance with another example, a method for determining a projectedremaining lifetime for a component of a process control device isprovided. The method may include receiving a projected lifetime profilefor the component, where the projected lifetime profile is developedbased on previously-recorded performance data collected during operationof a reference component under conditions compatible with conditionsunder which the process control device is to operate, and wherein theprojected lifetime profile indicates a projected lifetime of thecomponent as a function of an operating parameter. The method mayinclude receiving current data on the operating parameter for thecomponent during operation of the process control device. The methodfurther includes analyzing that current data and the projected lifetimeprofile to determine a projected remaining lifetime for the component.The method may further include determining an operator notificationstate of the component based the determined projected remaininglifetime. In some examples, notification state data are communicated toremote personnel, such as a process control device operator ormaintenance personnel, to schedule maintenance on the component.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram of a process plant configured to receive andcoordinate data transfer between many functional areas of the plant;

FIG. 2 is a block diagram of an example process control device used in aprocess control system, where the example process control device is avalve assembly having an embedded integrated diagnostics module;

FIG. 3 is a block diagram of another example process control device usedin a process control system, where the example process control device isa valve assembly and a remote computer contains an integrateddiagnostics module;

FIG. 4 illustrates an example of the valve assembly of FIGS. 2 and 3showing various valve components that may be profiled;

FIG. 5 is a block diagram of an integrated diagnostics module used toprofile lifetimes of the valve components of FIG. 4; and

FIGS. 6A-6D are plots of projected lifetime profiles developed by theintegrated diagnostics module for each of the valve componentsidentified in FIG. 3.

DETAILED DESCRIPTION

Although the following text sets forth a detailed description ofnumerous different embodiments, it should be understood that the legalscope of the description is defined by the words of the claims set forthat the end of this patent. The detailed description is to be construedas exemplary only and does not describe every possible embodiment sincedescribing every possible embodiment would be impractical, if notimpossible. Numerous alternative embodiments could be implemented, usingeither current technology or technology developed after the filing dateof this patent, which would still fall within the scope of the claims.

Referring now to FIG. 1, a process plant 10 includes a number ofbusiness and other computer systems interconnected with a number ofcontrol and maintenance systems by one or more communication networks.

The process control system 12 and 14 may be, for example, DeltaV™controllers sold by Fisher-Rosemount Systems, Inc. of Austin, Tex. orany other desired type of controllers or DCS which My include anoperator interface 12A coupled to a controller 12B and to input/output(I/O) cards 12C which, in turn, are coupled to various field devicessuch as analog and Highway Addressable Remote Transmitter (HART) fielddevices 15. The process control system 14 may include one or moreoperator interfaces 14A coupled to one or more distributed controllers14B via a bus, such as an Ethernet bus. The controllers 14B areconnected via I/O devices to one or more field devices 16, such as forexample, HART or Fieldbus field devices or any other smart or non-smartfield devices including, for example, those that use any of thePROFIBUS®, WORLDFIP®, Device-Net®, AS-Interface and CAN protocols. As isknown, the field devices 16 may provide analog or digital information tothe controllers 14B related to process variables as well as to otherdevice information. The operator interfaces 14A may store and executetools available to the process control operator for controlling theoperation of the process including, for example, control optimizers,diagnostic experts, neural networks, tuners, etc.

Still further, maintenance systems, such as computers executing an assetmanagement application or any other device monitoring and communicationapplications may be connected to the process control systems 12 and 14or to the individual devices therein to perform maintenance andmonitoring activities. For example, a maintenance computer 18 may beconnected to the controller 12B and/or to the devices 15 via any desiredcommunication lines or networks (including wireless or handheld devicenetworks) to communicate with and, in some instances, reconfigure orperform other maintenance activities on the devices 15. Similarly, assetmanagement applications may be installed in and executed by one or moreof the user interfaces 14A associated with the distributed processcontrol system 14 to perform maintenance and monitoring functions,including data collection related to the operating status of the devices16.

The process plant 10 also includes various rotating equipment 20, suchas turbines, motors, etc. which are connected to a maintenance computer22 via some permanent or temporary communication link (such as a bus, awireless communication system or hand held devices which are connectedto the equipment 20 to take readings and are then removed). Themaintenance computer 22 may store and execute known monitoring anddiagnostic applications 23 provided by, for example, CSI 2140 MachineryHealth Analyzer from CSI-Computational Systems, Inc. of Knoxville, Tenn.or other any other known applications used to diagnose, monitor andoptimize the operating state of the rotating equipment 20. Maintenancepersonnel usually use the applications 23 to maintain and oversee theperformance of rotating equipment 20 in the plant 10, to determineproblems with the rotating equipment 20 and to determine when and if therotating equipment 20 must be repaired or replaced.

To facilitate communications regarding maintenance of the variousequipment (i.e., process control devices), in the illustrated example, acomputer system 30 is provided which is communicatively connected to thecomputers or interfaces associated with the various functional systemswithin the plant 10, including the process control functions 12 and 14,the maintenance functions such as those implemented in the computers 18,14A, 22 and 26 and the business functions. In particular, the computersystem 30 is communicatively connected to the process control system 12and to the maintenance interface 18 associated with that control system,is connected to the process control and/or maintenance interfaces 14A ofthe process control system 14, and is connected to the rotatingequipment maintenance computer 22, all via a bus 32. The bus 32 may useany desired or appropriate local area network (LAN) or wide area network(WAN) protocol to provide communications.

As illustrated in FIG. 1, the computer 30 is also connected via the sameor a different network bus 32 to business system computers andmaintenance planning computers 35 and 36, which may execute, forexample, enterprise resource planning (ERP), material resource planning(MRP), accounting, production and customer ordering systems, maintenanceplanning systems or any other desired business applications such asparts, supplies and raw materials ordering applications, productionscheduling applications, etc. The computer 30 may also be connected via,for example, the bus 32, to a plantwide LAN 37, a corporate WAN 38 aswell as to a computer system 40 that enables remote monitoring of orcommunication with the plant 10 from remote locations.

Generally speaking, the computer 30 stores and executes an assetmanagement system 50 that collects data and other information generatedby the process control systems 12 and 14, the maintenance systems 18, 22and 26 and the business systems 35 and 36 as well as informationgenerated by data analysis tools executed in each of these systems.

Also, generally speaking, one or more user interface routines 58 can bestored in and executed by one or more of the computers within the plant10. For example, the computer 30, the user interface 14A, the businesssystem computer 35 or any other computer may run a user interfaceroutine 58. Each user interface routine 58 can receive or subscribe toinformation from the asset management system 50 and either the same ordifferent sets of data may be sent to each of the user interfaceroutines 58. Any one of the user interface routines 58 can providedifferent types of information using different screens to differentusers. For example, one of the user interface routines 58 may provide ascreen or set of screens to a control operator or to a business personto enable that person to set constraints or to choose optimizationvariables for use in a standard control routine or in a controloptimizer routine. The user interface routine 58 may provide a controlguidance tool that enables a user to view the indices created by theindex generation software 51 in some coordinated manner. This operatorguidance tool may also enable the operator or any other person to obtaininformation about the states of devices, control loops, units, etc. andto easily see the information related to the problems with theseentities, as that information has been detected by other software withinthe process plant 10. The user interface routine 58 may also provideperformance monitoring screens using performance monitoring dataprovided by or generated by the tools 23 and 27, the maintenanceprograms such as an asset management application or any othermaintenance programs, or as generated by the models in conjunction withthe asset management system 50. Of course, the user interface routine 58may provide any user access to and enable the user to change preferencesor other variables used in any or all functional areas of the plant 10.

The plant 10 illustrates various process control devices (e.g., devices14, 15, 16, 20, and 25), that may degrade in performance over time andrequire maintenance. Certain process control devices, such as a controlvalves or other devices, are used to modulate or control fluid flowwithin the process control system, under the control of process controlsystems 12 and 14. (Fluids, in this case, may include gaseous fluidssuch as compressed nitrogen gas, etc.) These are provided by way ofexample, as it should be understood by one of ordinary skill in the artthat although the example embodiments described herein are based uponpneumatic control valves, other process control devices such as pumps,electrically-actuated valves, and dampers will also affect process plantoperation and may be included in the techniques described herein.

In general, process control devices, such as control valve assemblies,may be positioned in conduits or pipes to control fluid flow by alteringthe position of a moveable element, such as a valve plug within thecontrol valve, using an attached actuator and positioner. Theadjustments to the control element may be used to influence some processcondition to maintain a selected flow rate, a pressure, a fluid level ora temperature.

A control valve assembly is typically operated from a regulated sourceof pneumatic fluid pressure, such as air from a plant compressor. Thisfluid pressure is introduced into the actuator (such as a spring anddiaphragm actuator for sliding stem valves or a piston actuator forrotary valves) through a positioner or valve control instrument whichcontrols the fluid pressure in response to a signal received from theprocess control system. The magnitude of the fluid pressure in theactuator determines the movement and position of the spring anddiaphragm or piston within the actuator, thereby controlling theposition of a valve stem coupled to the moveable element of the controlvalve. For example, in the spring and diaphragm actuator, the diaphragmmust work against a bias spring, to position the moveable element (i.e.,valve plug) within a valve passageway between the inlet and the outletof the control valve to modify flow within the process control system.The actuator may be designed so that increasing fluid pressure in thepressure chamber either increases the extent of the moveable elementopening or decreases it (e.g., direct acting or reverse acting), theformer situation being assumed herein. While these descriptions may beapplicable to a sliding stem valve, corresponding components andoperations would apply to rotary valves.

FIG. 2 illustrates a general control valve assembly 100 that may be usedin the process control system 12 or 14. A control valve 102 may have amoveable element, such as valve stem and valve plug (not shown), that isselectively positioned by an actuator 104 being controlled by apositioner to modify process flow. It is understood by one of ordinaryskill in the art that an indication of the position of the valve plugmoveable element is provided through a position sensor 106, which may beintegrated into the valve position controller 108 or may be a standalonepositioner transmitter. The control valve 102 creates a variable orificewithin the flow path of the process control system to control the flowof process materials in the process control system. The process controlsystem may generally use transmitter 110 to detect a process variable tocharacterize the process. The process variable may be transmitted backto a process device controller 112 directing the operation of theprocess plant to control the process.

A valve controller 114 includes the valve position controller 108, theposition sensor 106 and may also include an actuator control signalgenerator 116, that may include, for example, an electro-pneumatic stage(not shown) that is controlled by a microcomputer provided therein, thatgenerates an output signal from the valve position controller 108 todrive the actuator 104. It should be appreciated by one of ordinaryskill in the art that the actuator may be an electric actuator (notshown) and the actuator control signal generator may provide an electriccontrol signal to control or modify the position of the electricactuator. The actuator control signal generator 116 converts the outputsignal from valve position controller 108 to the corresponding controlvalue to be established in the actuator 104. The position sensor 106 maymonitor actuator 104 for position input information (via the actuatorstem position) or control valve 102 (via the valve stem), shown as adotted line.

In operation, a user interacts with the control valve 102 and process118 at a user process control interface 120 that provides commands tothe process controller 112 responsible for the control of the entireprocess, where the process controller 112 is in communication with othercontrol devices (not shown) used in the plant for process control. Theprocess controller 112 may translate the input commands supplied by theuser at interface 120 into setpoint signal commands. The setpoint signalcommands may then be sent to valve controller 114, and specifically tothe valve position controller 108. The valve position controller 108 mayhave therein the microcomputer described above. The microcomputer may beprogrammed to follow an algorithm for controlling the control valve 102in response to received setpoint signal commands and directing theactuator control signal generator 116 to generate a correspondingcontrol signal in the actuator 104 for positioning the control valve102.

In the system of FIG. 2, increases in magnitudes of the setpointcommands may cause corresponding increases in the pneumatic pressureprovided by the actuator control signal generator 116 in the valvecontroller 114, thereby effecting, via the actuator 104, correspondingincreases in the opening controlled by the moveable element of thecontrol valve 102. The resulting position of the moveable element mayhave an effect on the process and, accordingly, on the process variablemonitored and detected by the process variable transmitter 110. Theprocess variable transmitter 110 transmits a representative signal ofthe process variable back to process controller 112. One of ordinaryskill in the art will understand that the process controller 112 usesthe representative signal as an indication of the status of the processfor feedback to control the system.

As discussed above, the process controller 112 may be in communicationwith other control devices used in the plant for process control. Theprocess controller 112 may also include or may be connected to acomputer having general computing elements such as a processor orprocessing apparatus, a memory, an input device and a display device(e.g., monitor). The processor may be connected to the memory, thedisplay device, and the input device, as known by those skilled in theart. Also, the computer may include a network interface for connectingbetween a network and the computer to provide communicationtherebetween. In one embodiment, the computer may form a portion of theprocess controller, such as in a digital process controller. In anotherembodiment, the user process control interface may represent thecomputer. Alternatively, the computer may be connected on a network tothe process controller but be physically remote from the processcontroller.

The valve controller 114 also includes or, alternatively, receivesinformation from, an operating conditions sensor 122 that monitors oneor more operating conditions for the valve 102 and/or the valve actuator104 and/or one or more environmental conditions under which the valve102 is operating. The operating conditions sensor 122 may be any sensoror transmitter that detects or otherwise monitors an operating conditionat or near the valve 102 or the valve actuator 104. For example, theoperating conditions sensor may monitor a temperature of a fluid flowingthrough the valve 102, a temperature of fluid operating the valveactuator 104, a temperature of fluid moving through the positioncontroller 108, an ambient air temperature of the valve 102, the valveactuator 104, or the valve position controller 108, a pH level of any ofthe fluids mentioned above, a pressure (upstream or downstream) of anyof the fluids above, a salinity or viscosity of any of the fluids above,etc. The operating condition sensor 122 is coupled to provide sensedoperating condition data to the valve position controller 108 foraffecting control of the valve 102 and to an integrated diagnosticsmodule 124. In some embodiments, operating condition sensor 122transmits data to a data historian or other centralized data collectionelement, and the diagnostics module 124 retrieves the operatingcondition data therefrom.

Multiple operating conditions sensors 122 and/or multiple positionsensors 106 may be disposed throughout the system shown in FIG. 2 todetect and/or measure characteristics of the control device and systemand may provide this characteristic information or data to the computeror process device controller 112 for display on the display deviceelement. In one embodiment, the sensor data from both sensors 106 and122 are collected by the integrated diagnostics module 124, which mayinclude a computer processor and memory. In some examples, a diagnosticmonitor 126 coupled to the module 124 represents a computer displaydevice that displays the sensor data or data output by the module 124.The input device element of the computer may be, for example, akeyboard, a touchpad, mouse, trackball, a lightpen, microphone (e.g.,for voice command inputs), etc. Note also that various embodiments ofthe claimed method and system described below may be implemented as aset of instructions in the processor of the computer for execution, asknown by those skilled in the art.

The integrated diagnostics module 124 develops and implements prognosticalgorithms for process control devices to predict the end of usable lifefor these devices and/or various components thereof. Example processcontrol devices exemplified herein are valve assemblies. However, morebroadly, an integrated diagnostics module may be used with any processcontrol device that experiences mechanical wear or fatigue over time,including devices that modulate fluid flow in a process, such as valves,pumps, and dampers, and may be implemented to predict the end of useablelife for the components of each and any of these devices.

The integrated diagnostics module 124 assembles prognostics algorithmsfor components that form the process control device and from whichusable remaining lifetime (e.g., remaining cycle life time, projectedmaintenance date) data may be determined. As discussed further below,the integrated diagnostics module 124 may derive these algorithms fromdocumented average or minimum service life of multiple process controldevices of the same type and construction materials, as used in a givenapplication, from laboratory data collected in a manner that most nearlyapproximates field service conditions (e.g., operating environment),and/or from historical data of identical or similar devices, or parts ofdevices, in the plant or environment in which the device or part isinstalled. Such algorithms, therefore, may take into account thosecomponents that normally fail by mechanical wear or fatigue and whichcan be characterized as having a fixed or average lifetime when new. Forexample, when projecting cycle life, the integrated diagnostics module124 may decrement a fixed or average cycle life, by each cycleexperienced during operation. Such a decrement would occurautomatically, for example, in response to an automatic sensor at theprocess control device or from operator input. As another example, theintegrated diagnostics module 124 may decrement a fixed or averagemovement life (e.g., of a seal around a valve stem) by the cumulativemovement of a part (e.g., the valve stem) as sensed by the positionsensor 104 in the valve actuator 104 or in the valve 102, as controlledby the actuator control signal generator 116, as controlled by the valveposition controller 108, or even as controlled by the process controller112.

In some examples, the remaining lifetime is determined based at least inpart on data from sensors (e.g., sensors 106 and 122) measuring normaloperating conditions, where the data are collected at periodicdetermined time intervals, or on a continuous basis, or in response tosome triggering event. In some examples, the remaining lifetime isdetermined based at least in part on information from the processcontroller 112, the valve position controller 108, and/or the valveactuator 104. For instance, the remaining lifetime may be determining,in some embodiments, according to the one or more operating conditionsas sensed by the sensor 122 and according to the number of open/closecycles as instructed by the process controller 112 (as opposed toreceiving the number of open/close cycles from the actuator 104 or theposition sensor 106).

The integrated diagnostics module 124 is able to determine remaininglifetime for each replaceable component of the process control device(e.g., plugs, seals, bushings, bearings, etc.), as well as for theprocess control device as a whole. In either case, the remaininglifetime may be based solely on characteristics of the particularprocess control device or components in question or based oncharacteristics measured from other processing plant devices or data.The latter may include other devices operating in coordination with thedevice in question, as well general operating conditions of theprocessing plant. The particular remaining lifetime data may be storedin a computer readable memory device, for example, by a smart positionerdevice in a valve configuration, such as within the valve controller 114of FIG. 2.

The integrated diagnostics module 124 is able to communicate with aremote computer, such as a system controller 12 or 14, through acommunication interface 128 that may be a wired or wirelesscommunication interface, which remote computer may, in some instances,take some process control action (e.g., adjusting the use of a valve—forexample, the speed or frequency of actuation—to prolong the life of acomponent of the valve, switching to a redundant device/flow path, etc)based on data received from the integrated diagnostics module 124.

As illustrated in FIG. 2, and as described above, the integrateddiagnostics module 124 may receive a variety of inputs in variousimplementations. Among the inputs are inputs from one or more operatingconditions sensor(s) 122, one or more position sensor(s) 106, one ormore process variable transmitter(s) 110, the process controller 112,and the communication interface 128. Each of the operating conditionssensors 122 may sense a different parameter (e.g., temperature,pressure, viscosity, flow rate, etc.), or may sense the same parameteras another sensor, but at a different location (e.g., upstream anddownstream pressure, temperature of fluid flowing through the valve 102and temperature of fluid controlling the actuator 104, etc.). Each ofthe one or more position sensors 106 may sense a position of a differentelement (e.g., the position of a valve stem and the position of anactuator stem). The integrated diagnostics module 124 may also include(e.g., as stored in a memory device) or retrieve/receive (e.g., via thecommunication interface 128) data and/or algorithms to use indetermining the remaining useful life of the device or the components ofthe device.

In the example of FIG. 2 the integrated diagnostics module 124 isembedded within the valve assembly 100. For example, the module 124 maybe implemented by an on-board processor (of the controller 114), or byinstructions being executed by such a processor, in a smart processcontrol device. FIG. 3 illustrates another example configuration, with avalve assembly 100′, having similar features to that of valve assembly100, except that an integrated diagnostics module 150 is containedwithin a remote computer system 152, such as a multiplexed hostcomputer, a DCS system, a plant asset management system (such as theasset management system 50), or any combination of these. Thecommunication interface 128′ packages the operating conditions data fromsensor(s) 122′ and the sensor(s) 106′ and transmits them to the remotecomputer system 152 for profiling by the integrated diagnostics module150.

FIG. 4 is an example process control device in the form of a valveassembly 200 made up of various components, which each have potentiallydifferent lifetime profiles that will be determined by an integrateddiagnostics module (e.g., the integrated diagnostics module 124). In theillustrated examples these lifetime profiles are cycle lifetimeprofiles, because they depend on the number of operating cycles thevalve experiences (e.g., the number of experienced fully open/closeoperations of the number of experienced partially open/closeoperations). In the illustrated example, the valve assembly 200 isformed of a series of components that may be profiled using lab testingdata or previously collected historical data of actual in-use valveassemblies. In this way, lifetime profiles may be developed from realworld data reflecting the particular conditions experienced in aprocessing plant installation. The particular components illustratedinclude a diaphragm header component 202 and a shaft receptacle 204connected to a seal component 206 and engaged with a valve body 208through packing gland (bushings, or bearings) component 210.

A valve controller 212 corresponding to the valve controller 114, inwhole or in part, controls valve actuation and position. An integrateddiagnostics module within the valve controller 212 collects variousoperating data and profile data to determine a cycle lifetime profilefor each of these various components, using a prognostic algorithm. Insome examples, such as FIG. 2, the prognostic algorithm is applied by anon-board processor within a dedicated positioner instrument, within avalve controller. In some examples, such as FIG. 3, the prognosticalgorithm is applied by a multiplexed host computer in communicationwith the valve controller 212, such as the computer systems 30, 35 or36. In yet other examples, a distributed process control (DCS) system ora plant asset management system, such as the asset management system 50,in communication with the controller 212 may be used. In yet otherexamples, a combination of these analysis configurations may be used,which may be beneficial when component cycle life from numerousdifferent sources is used.

FIG. 5 illustrates an example integrated diagnostics module 400(corresponding, for example, to the integrated diagnostics module 124)as may be contained within the valve controller 312 or the remotecomputer system 152. The module 400 is configured to have access to adevice descriptor 402 that identifies the particular process controldevice under analysis (e.g., valve assembly, pump assembly, damper,etc.). The device descriptor 402 may be embedded within the processcontrol device either by the manufacturer or by a customer and may be afile, stored in a memory device, that is fixed or re-writeable, invarious embodiments. In some examples, the device descriptor 402 is are-writeable or otherwise configurable part of the user process controlinterface 120, so as to facilitate manual identification or selection ofthe particular process control device to be profiled. In any event, thedevice descriptor 402 may be stored locally at the process controldevice or on a remote computer system, such as the systems 12, 14, 30,35, or 36.

The device descriptor 402 accesses a list file 404 that identifies thecomponents forming the process control device and that have profilablelifetime, and may identify for each component any data needed to createa lifetime profile for the component, as described below. In the exampleof FIG. 4, the list file 404 identifies the diaphragm header component302, the shaft receptacle 304, the seal component 306, and the packinggland component 310 as profilable components of the valve assembly 300.

In some embodiments, the components listed in the list file 404 dependupon the type of process control device. For a sliding stem valveassembly, for example, a list file 404 may identify any one or more ofthe following components that will experience mechanical wear or fatigueduring operation: actuator diaphragm or piston and rod seals, actuatorguide bushings or bearings, valve packing, valve stem, stem or plugguide bushings or bearings, valve plug balance seals, valve plug, valvecage, bellows seals, and/or actuator springs. For a rotary valveassembly, the list file 404 may identify actuator diaphragm or pistonand rod seals, actuator guide bushings or bearings, actuator rod endbearings, valve shafts, valve bearings or bushings, seals, disks, balls,segmented balls or plugs, and/or actuator springs.

In other embodiments, the list file 404 may include all of thecomponents for a particular line of devices of a particular type, or allof the components for a manufacturers entire product line. In theseembodiments, the integrated diagnostics module 400 may retrieve from thelist file 404 only data relating to the devices identified by the devicedescriptor 402. For example, the device descriptor 402 may identify(e.g., by being programmed/configured by an operator or technician) aparticular type of valve actuated by a particular type of actuator. Themodule 400 may then retrieve from the device descriptor 402 data relatedto components that are associated with the particular actuator and valvetypes. In some embodiments, the list file 404 may be stored remotely,such as on a server accessible via a communication network such as a LAN(e.g., where the list file 404 is stored on a plant server) or theInternet (e.g., where the list file 404 is stored on a devicemanufacturer server).

The list file 404 may also identify fatiguing accessories mounted to avalve assembly or valve positioner, such as volume boosters, solenoids,trip valves, limit switches, position transmitters, instrument supplypressure regulators, and pneumatic tubing.

While a single list file 404 is shown in FIG. 5, in other examples,multiple list files may be used, for example, to allow standard valvecomponents to be listed in one list file and fatigue accessories listedin another list file.

Where multiple components are stored in the device descriptor 402,different list files 404 for each part may be accessed under instructionfrom the integrated diagnostics module 400.

The list files 404 may be initiated and updated by a device manufactureror customer, from operator input. For example a GUI interface may beprovided (by interface 120) to an operator to allow for selectingpre-existing stored, component entries, as well as for adding and/ordeleting component entries. Formation of the list file 404, therefore,may be performed prior to operation of the process control device. Thelist file 404 may be updated to include additional components addedduring operation of the part assembly. Such updating may occur throughmanual entry by an operator or automatically, for example, for systemsin which as accessories are added to a part assembly those accessoriesare automatically detected by the part controller.

In addition to identifying components, the list file 404 may identify,for each of the listed components, an operating parameter that affectsthe mechanical wear or fatigue of that component during operation of thedevice. Because the lifetime of each component may be affected bydifferent operating conditions, in some examples, the list file 404identifies the different operating parameters that are to be accessed bythe integrated diagnostics module 400 in developing a component lifetimeprofile. For example, a valve positioner may fatigue in response tonumerous parameters, such as, current to pressure ratio (I/P)experienced by the valve nozzle/flapper, the piezo crystal, or themoving solenoid component. Additional parameters include pressure on apressure relay, the position of linkages in a valve, the position ofvarious feedback devices, whether such feedback is from a potentiometer,encoder or resolver device. Generally, these operating parametersidentify the metrics that are to be sensed and evaluated using aprognostic algorithm to determine a lifetime profile for a component andfor the process control device overall.

As discussed further below, the integrated diagnostics module 400 mayalso access stored historical data 406 having previously obtainedoperating data, maintenance data, mean time to failure, or other data onthe device and its components.

In the illustrated example, the integrated diagnostics module 400 alsoaccesses lab testing data 407 for the process control device andcorresponding components listed in the list file 404. In other examples,only one of the lab testing data 407 or the historical data 406 isaccessed by the module 400.

In the configuration of FIG. 2 the historical data 406 and the lab testdata 407 may be stored locally or accessed remotely through thecommunication interface 128. In the configuration of FIG. 3 thehistorical data 406 and lab test data 407 may be stored at the remotecomputer system 152, e.g., accessible by the computer system 12, 14, 30,35, and/or 36.

To diagnose operations of a process control device and develop lifetimeprofiles, the integrated diagnostics module 400 includes a profiler 408that collects and stores historical data 406 and lab testing data 407for at least some of the components listed in the list file 404. Fromthis data the profiler 408 determines a lifetime profile for each of theidentified components and based on the identified correspondingoperating parameter(s) associated with that component. The profiler 408may store previously developed lifetime profiles or may construct them.

The determined lifetime profiles are stored in a plurality of differentprofiles 410, as illustrated. Example profiles are illustrated in FIGS.6A-6D.

FIG. 6A is a lifetime profile developed by the profiler 408, for thediaphragm component 302, indicating the lifetime (in hours) of adiaphragm's oxidation level as a function of temperature and showing alinear downward sloping profile. FIG. 6B illustrates a cycle lifetimeprofile for the packing gland component 310, indicating the amount ofleakage (measured in parts per million) as a function of operationcycles for the component. The cycle lifetime profile includes profiledata for at least four different packing gland components, collectedfrom the historical data 406 and/or the lab testing data 407.

When the profiler 408 is provided with multiple data sets, the profile408 may average the data to determine a mean time to failure, i.e.,where the data sets correspond to the same operating parameters. In someexamples, the stored data may include historical or lab testing datataken at different operating parameters (e.g., one data set collectedshowing actual lifetime as a function of pressure another taken showingactual lifetime as a function of temperature). In such cases, theprofiler 408 may develop profiles for a component at each of thedifferent operating parameters.

FIG. 6C is a cycle lifetime profile developed for the seal component306, indicating the amount of leakage (in ppm) as a function of thenumber of operating cycles. FIG. 6D is a cycle lifetime profile for theshaft component 304, indicating the percentage failure as a function ofthe number of operating cycle. While four cycle life profiles are shown,for example purposes, it will be appreciated that any number of cyclelife profiles may be stored in the profiler 408 and used by theintegrated diagnostics module 400.

In some examples, the profiler 408 is pre-populated with lifetimeprofiles for components identified in the list file 404, for example,where the components have been previously profiled, at similar operatingconditions. In either case, the profiler 408 is able to update thelifetime profiles based on elapsed time, the number of cycles, or otherparameters. For example, for a valve assembly, the profiler 408 mayreceive a cycle count from a valve positioner or valve state counter414. The profiler 408 may receive a temperature value from a temperaturesensor (not shown). The profiler 408 may receive position data for thevalve from a position sensor. The profiler 408 is able to adjust thelifetime profiles for the components and for the overall valve assembly,based on these parameters.

The integrated diagnostics module 400 collects sensor data (e.g., fromsensors 106 and 122) and stores operating conditions for the processcontrol device in an operational data module 410. The operatingconditions may be real time sensed data corresponding to the operatingparameters identified in the list file 404. As discussed above, for avalve assembly, the sensed data may include any parameter that willaffect the mechanical wear or fatigue of the listed components or thevalve assembly as a whole, including current to pressure (I/P)experienced by the valve nozzle/flapper, the piezo crystal, or themoving solenoid component, pressure, component temperature, ambienttemperature, fluid rate, leakage, oxidation level, the position oflinkages in a valve, and the position of various feedback devices.

The operating data from the module 410 are provided, along with thelifetime profiles from the profiler 408, to a remaining lifetimeanalyzer 412 that analyzes current operating data against thecorresponding profiles, for the components, to determine a projectedremaining lifetime each component and/or for the entire process controldevice. For the latter, the analyzer 412 applies a multifactoralanalysis algorithm to the received data, to determine the projectedlifetime, based on the projected life times of each of components. Theprojected remaining lifetime values may be cycle lifetime values, whenindicated as a function of remaining operating cycles for a valveassembly, for example. While in other examples, the projected remaininglifetime values may be measured or indicated in a counter time orprojected failure date. For example, the lifetime analyzer 412 mayreceive the cycle count value from the counter 414 which it thencompares to the profiles from the profiler 408 to determine a projectedremaining cycle lifetime.

The analyzer 412 may include a confidence determination that assesseswhether enough operational data and profiles have been provided to it tomake a sufficiently accurate determination of projected cycle life forthe process control device. A warning indication may be provided ifinsufficient sensor data are collected and a remaining projectedlifetime cannot be determined for a given valve component.

The analyzer 412 provides the projected cycle life time determination toa decision module 418 that determines a notification state for thedetermination. In an example, the notification state has one of threeconditions: (i) NORMAL, indicating no required maintenance; (ii)MAINTENANCE, indicating that maintenance or replacement will be neededat the next scheduled service; or (iii) ALERT, indicating thatmaintenance or replacement is needed before the next scheduled service.An alert mechanism may be provided on the process control device toindicate the notification state, e.g., with color coded lights or adisplay. The decision module 418 is coupled to a communication interface420 (which may be the communication interfaces 128 or 128′) forcommunicating the notification state and projected lifetimedetermination to a remote computer or operator, such as the remotecomputer systems 12, 14, 30, 35, and/or 36, shown in FIG. 1. In additionto providing a local indication of notification state, the communicationinterface 420 may be a wired or wireless communication interfaceproviding of the indication of the notification state to a hostcomputer, DCS, remote computer, or the like, which, in at least someembodiments, causes a controller to modify the operation of the processplant according to the notification state, for example by decreasing thefrequency or speed of actuation, or by switching to a redundant flowpath.

In this way, the present techniques may provide a warning message to acontrol room operator, maintenance department or reliability engineeringdepartment, where the warning message quantifies the prognosticatedremaining time to failure of the component. In some examples, thewarnings may be set far enough in advance that they appear during ascheduled maintenance outage occurring before the projected failuretime. This would give personnel a chance to plan for service orreplacement of the component before the expected failure. The warningmessages may include repair data such as recommend spare parts orrecommended service actions. The warning messages may be provided to aremote computer system to facilitate manual repair ordering or to enableautomatic order of replacement parts from a component manufacturer. Thewarning message may be provided to business system computers andmaintenance planning computers 35 and 36, which may not only facilitateordering or replacement parts, as described, but also scheduling suchreplacement, e.g., during an already scheduled maintenance outage orduring a future maintenance outage.

In some examples, the timing of the warning message may be set by theoperator of the process control device to be longer or shorter thanpreviously set depending upon the assessed condition of the processcontrol device and the impending service projection. For example, theintegrated diagnostics module 400 may be configured to provide morefrequent warning messages as the projected failure point nears. Thetiming of the warning messages may also be controlled after theinitially warning message has been sent.

As a process control device's performance deteriorates, and morespecifically, as the performance of the various components deteriorates,the projected cycle life time data, as well as the eventual actual cyclelife time data, are stored in the historical data 406. From here datasuch as the MTTF and MTBF for components may be stored for laterreference by the integrated diagnostics module 400 or a module foranother device, thereby improving the accuracy of future cycle lifetimeprojections. In some examples, such historical data may be shared withmanufactures, through dedicated wired or wireless communications, withthe component owner's consent. For example, such data may be provided bygranting access to a shared database, website or wireless network,storing a copy of the historical data 406. Providing this data allowsfor eventually replacing lab data with data developed usingmore-reliable algorithms at the manufacturer end.

The prognostic capabilities of the system herein can be customized,based on field experience for a specific application. As with theprofiler 408, the criteria of the lifetime analyzer 412 and decisionmodule 418 can be set based on numerous parameters such as elapsed time,valve travel, cycles, temperature, etc. In this way diagnosticcapabilities may be based on field experience in prior installations anddata collected by the device controller.

In various embodiments, a module may be implemented in hardware orsoftware. For example, a module implemented in hardware may comprisededicated circuitry or logic that is permanently configured (e.g., as aspecial-purpose processor, such as a field programmable gate array(FPGA) or an application-specific integrated circuit (ASIC)) to performcertain operations. A module implemented in software may compriseprogrammable logic or circuitry (e.g., as encompassed within ageneral-purpose processor or other programmable processor) that istemporarily configured by software to perform certain operations. Itwill be appreciated that the decision to implement a module in hardware,in dedicated and permanently configured circuitry, or in software, intemporarily configured circuitry (e.g., configured by software), may bedriven by cost and time considerations.

Accordingly, the term “hardware module” should be understood toencompass a tangible entity, be that an entity that is physicallyconstructed, permanently configured (e.g., hardwired), or temporarilyconfigured (e.g., programmed) to operate in a certain manner or toperform certain operations described herein. As used herein,“hardware-implemented module” refers to a hardware module. Consideringembodiments in which hardware modules are temporarily configured (e.g.,programmed), each of the hardware modules need not be configured orinstantiated at any one instance in time. For example, where thehardware modules comprise a general-purpose processor configured usingsoftware, the general-purpose processor may be configured as respectivedifferent hardware modules at different times. Software may accordinglyconfigure a processor, for example, to constitute a particular hardwaremodule at one instance of time and to constitute a different hardwaremodule at a different instance of time.

Hardware modules can provide information to, and receive informationfrom, other hardware modules. Accordingly, the described hardwaremodules may be regarded as being communicatively coupled. Where multipleof such hardware modules exist contemporaneously, communications may beachieved through signal transmission (e.g., over appropriate circuitsand buses) that connects the hardware modules. In embodiments in whichmultiple hardware modules are configured or instantiated at differenttimes, communications between such hardware modules may be achieved, forexample, through the storage and retrieval of information in memorystructures to which the multiple hardware modules have access. Forexample, one hardware module may perform an operation and store theoutput of that operation in a memory device to which it iscommunicatively coupled. A further hardware module may then, at a latertime, access the memory device to retrieve and process the storedoutput. Hardware modules may also initiate communications with input oroutput devices, and can operate on a resource (e.g., a collection ofinformation).

The various operations of example methods described herein may beperformed, at least partially, by one or more processors that aretemporarily configured (e.g., by software) or permanently configured toperform the relevant operations. Whether temporarily or permanentlyconfigured, such processors may constitute processor-implemented modulesthat operate to perform one or more operations or functions. The modulesreferred to herein may, in some example embodiments, compriseprocessor-implemented modules.

Similarly, the methods or routines described herein may be at leastpartially processor-implemented. For example, at least some of theoperations of a method may be performed by one or processors orprocessor-implemented hardware modules. The performance of certain ofthe operations may be distributed among the one or more processors, notonly residing within a single machine, but also deployed across a numberof machines. In some example embodiments, the processor or processorsmay be located in a single location (e.g., within a home environment, anoffice environment or as a server farm), while in other embodiments theprocessors may be distributed across a number of locations.

Still further, the figures depict preferred embodiments of a map editorsystem for purposes of illustration only. One skilled in the art willreadily recognize from the following discussion that alternativeembodiments of the structures and methods illustrated herein may beemployed without departing from the principles described herein.

Upon reading this disclosure, those of skill in the art will appreciatestill additional alternative structural and functional designs for asystem and a process for identifying terminal road segments through thedisclosed principles herein. Thus, while particular embodiments andapplications have been illustrated and described, it is to be understoodthat the disclosed embodiments are not limited to the preciseconstruction and components disclosed herein. Various modifications,changes and variations, which will be apparent to those skilled in theart, may be made in the arrangement, operation and details of the methodand apparatus disclosed herein without departing from the spirit andscope defined in the appended claims.

What is claimed is:
 1. A method for developing a projected lifetimeprofile for a component of a valve assembly, the method comprising:receiving, at an integrated diagnostics module of the valve assembly, anidentification of the component of the valve assembly, wherein thecomponent is capable of experiencing mechanical wear or fatigue, overtime, during operation of the valve assembly; receiving, at theintegrated diagnostics module of the valve assembly, an operatingenvironment parameter corresponding to the component, wherein themechanical wear or fatigue of the component varies with changes in theoperating environment parameter; receiving, at the integrateddiagnostics module of the valve assembly, previously-recordedperformance data of a reference component of another valve assembly, thereference component having an identical or similar type as thecomponent, where the previously-recorded performance data were collectedduring operation of the reference component under conditions compatiblewith conditions corresponding to the same operating environmentparameter under which the component of the valve assembly is to operate;developing, in a profiler of the integrated diagnostics module of thevalve assembly, the projected lifetime profile for the component,wherein the profiler is configured to develop the projected lifetimeprofile for the component based on the previously-recorded performancedata and the operating environment parameter, wherein the projectedlifetime profile comprises a plurality of lifetime values correspondingto a plurality of values associated with the operating environmentparameter, and wherein the projected lifetime profile is a cyclelifetime profile for the component, indicating a desired lifetime of thecomponent based on a projected number of operating cycles of the valveassembly as a function of the operating environment parameter; andtransmitting, via a controller of the valve assembly, a control signalto the component of the valve assembly to adjust at least one ofactuation or position of the component to prolong a life of thecomponent using the projected lifetime profile.
 2. The method of claim1, further comprising: receiving previously-recorded performance datafor a plurality of reference components, each having previously-recordeddata collected under conditions compatible with conditions under whichthe valve assembly is to operate; and developing the projected lifetimeprofile of the component by determining an average projected lifetimeprofile of the component.
 3. The method of claim 1, further comprising:receiving previously-recorded performance data for a plurality ofreference components, each having previously-recorded data collectedunder conditions compatible with conditions under which the valveassembly is to operate; and developing the projected lifetime profile ofthe component by determining a minimum projected lifetime profile of thecomponent.
 4. The method of claim 1, wherein the previously-recordedperformance data are historical data collected from the referencecomponent operating under processing plant conditions corresponding tothe processing plant conditions under which the valve assembly is tooperate.
 5. The method of claim 1, wherein the previously-recordedperformance data are laboratory test data collected from testing thereference component under the conditions compatible with the conditionsunder which the valve assembly is to operate.
 6. The method of claim 1,wherein the component is a diaphragm component, a packing glandcomponent, a bushing component, a seal component, or a shaft componentof the valve assembly.
 7. The method of claim 6, wherein the operatingenvironment parameter for the component is pressure, flow rate,temperature, leakage, percent failure, valve position, flow rate, fluidlevel, current/pressure ratio, and actuator position.
 8. The method ofclaim 1, further comprising: receiving operating conditions forcomponent during operation of the valve assembly; and updating, in theprofiler, the projected lifetime profile for the component based on thereceived operating conditions.
 9. The method of claim 8, wherein thereceived operating conditions comprises data on at least one ofpressure, flow rate, temperature, leakage, percent failure, position,flow rate, fluid level, and current/pressure ratio.
 10. The method ofclaim 8, wherein the received operating conditions comprises data on atleast one of elapsed time and number of cycles.
 11. The method of claim1, further comprising: receiving, at the integrated diagnostics module,an identification of a plurality of components of the valve assembly;receiving, at the integrated diagnostics module, previously-recordedperformance data of a plurality of reference components, eachcorresponding to a different component of the valve assembly;developing, in the profiler, projected lifetime profiles for each of thecomponents based on the previously-recorded performance data; anddeveloping, in the profiler, a projected lifetime profile for the valveassembly based on the projected lifetime profiles for the components.12. The method of claim 1, wherein the integrated diagnostics module iscontained within the valve assembly.
 13. The method of claim 1, whereinthe integrated diagnostics module is stored remotely from the valveassembly and communicates with the process control device through acommunication link.
 14. The method of claim 1, wherein thepreviously-recorded performance data are stored remotely from theintegrated diagnostics module and received through a communication link.15. A method for determining a projected remaining lifetime for acomponent of a valve assembly, the method comprising: receiving, in anintegrated diagnostics module of the valve assembly, a projectedlifetime profile for the component, wherein the projected lifetimeprofile is developed based on an operating environment parameter andpreviously-recorded performance data collected during operation of areference component of another valve assembly, the reference componenthaving an identical or similar type as the component under conditionscompatible with conditions corresponding to the same operatingenvironment parameter under which the component of the valve assembly isto operate, wherein the projected lifetime profile comprises a pluralityof lifetime values corresponding to a plurality of values associatedwith the operating environment parameter, and wherein the projectedlifetime profile is a cycle lifetime profile for the componentindicating a desired lifetime of the component based on a projectednumber of operating cycles of the valve assembly as a function of theoperating environment parameter; receiving, at the integrateddiagnostics module of the valve assembly, current data on the operatingenvironment parameter for the component during operation of the valveassembly; analyzing, in a lifetime data analyzer, the current data onthe operating environment parameter for the component and the projectedlifetime profile for the component to determine a projected remaininglifetime for the component; and transmitting, via a controller of thevalve assembly, a control signal to the component of the valve assemblyto adjust at least one of actuation or position of the component toprolong a life of the component using the projected remaining lifetimefor the component.
 16. The method of claim 15, wherein the component isa diagram component, a packing gland component, a bushing component, aseal component, or a shaft component of the valve assembly.
 17. Themethod of claim 15, wherein the operating environment parameter for thecomponent is one of pressure, flow rate, temperature, leakage, percentfailure, valve position, flow rate, fluid level, current/pressure ratio,or actuator position.
 18. The method of claim 15, further comprising:determining an operator notification state of the component based on thedetermined projected remaining lifetime, wherein the operatornotification state is (i) normal, indicating that no action is neededfor maintenance of the process control assembly, (ii) maintenance,indicating that maintenance should be performed within a normalmaintenance window, or (iii) alert, indicating that maintenance shouldbe performed prior to the normal maintenance window.
 19. The method ofclaim 18, further comprising communicating notification state data tomaintenance personnel if the notification state is maintenance or alert.20. The method of claim 18, further comprising communicatingnotification state data to a remote computer or remote operator.
 21. Themethod of claim 18, further comprising: communicating notification statedata to a maintenance scheduler; and automatically schedulingmaintenance on the process control component based on the projectedremaining lifetime.
 22. The method of claim 21, further comprisingautomatically generating a maintenance order corresponding to ascheduled maintenance.
 23. The method of claim 18, further comprisingcommunicating notification state data to a remote computer or remoteoperator, wherein the notification state data include recommendreplacement parts and/or recommended service actions for performingmaintenance or replacement on the component.
 24. The method of claim 15,wherein the integrated diagnostics module is contained within the valveassembly.
 25. The method of claim 15, wherein the integrated diagnosticsmodule is in a remote computer system communicating with the valveassembly through a communication link.
 26. The method of claim 25,wherein the current data on the operating environment parameter arereceived to the remote computer system from the valve assembly throughthe communication link.